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Mother Nature is full of surprises, hiding several gems beneath its heart in the form of forests, mountains, rivers, etc. One of the treasures that human got as a gift are the forests which value more than anything presents on this earth in terms of its significance. Still, humans are not realizing the full potential of trees and driving deforestation with supersonic speed (see the example of Amazon forests in Brazil). One of such trees which might face extinction soon is Taxus baccata L. Also called Yew, the tree is the toolbox for various kinds of diseases since ancient times. It is important for the common people and the scientific community to understand the importance of the chemical constituents present in it in the form of alkaloids, flavonoids, and essential oils. Here in this review, we will shed the light on the natural products present in Yew and their applications, side effects, and medicinal properties. Afterward, we will discuss the ADME (absorption, distribution, metabolism, and excretion) of Yew constituents, as most of the part of the tree is toxic for human consumption. This review will give insight into the T. baccata species and will be helpful for the medicinal chemists to design new molecules for various cancers, fungal and microbial infections, and asthma.

The Himalayan Yew or Taxus baccata sub sp. wallichiana is the native of the Temperate belt of Himalayas known widely for its ethnomedical properties and especially for the production of an anti-cancerous compound Taxol but since the plant is an understory and in low population size, the production of Taxol in nature is very poor so it cannot meet the high demand of Taxol for medical use. Hairy root culture is known for its genetic and physiochemical stability and increased production of secondary metabolites as compared to cell suspension culture and with the use of low frequency sonication for 1–2 min, the rate of transformation can be increased thereby induing more hairy roots. In our study, when the combination of low frequency sonication for production of hairy roots was used it helped in development of the hairy root culture of Taxus baccata sub sp. wallichiana as an alternative for increased Taxol production. It was seen that the hairy root induction from the explants emerged when an effective co– infection method in presence of acetosyringone with sonication for 60 s was done. The increase in hairy root biomass was further done for 16 weeks in root induction media that was without acetosyringone. The methanolic extract of the biomass when quantified for total Taxol content produced around 12 mg of Taxol per gram of hairy root biomass of Taxus baccata sub sp. wallichiana which is 79% more than the natural production of 0.15 mg per gram of bark stating a possible alternative for Taxol production commercially in a large amount.

Poisoning from consumption of foraged alternative medicine products is an uncommon yet recognized occurrence. Here, presented is the case of a 40-year-old woman who was witnessed to collapse with labored breathing and subsequently died despite emergency medical personnel attendance and resuscitation efforts. Autopsy revealed the presence of plant matter that was visually identified as leaves from Taxus baccata - the English Yew. Isolation of alkaloids from the plant material and subsequent identification of the same alkaloids in the decedent's blood by liquid chromatography-tandem mass spectrometry indicated a toxicological cause of death. This case illustrates a collaborative team approach among subject matter experts to unexpectedly discover and then confirm the sudden death of this woman from T. baccata toxicity.

Taxol, a natural product derived from Taxus, is one of the most effective natural anticancer drugs and the biosynthetic pathway of Taxol is the basis of heterologous bio-production. Here, we report a high-quality genome assembly and annotation of Taxus yunnanensis based on 10.7 Gb sequences assembled into 12 chromosomes with contig N50 and scaffold N50 of 2.89 Mb and 966.80 Mb, respectively. Phylogenomic analyses show that T. yunnanensis is most closely related to Sequoiadendron giganteum among the sampled taxa, with an estimated divergence time of 133.4−213.0 MYA. As with most gymnosperms, and unlike most angiosperms, there is no evidence of a recent whole-genome duplication in T. yunnanensis. Repetitive sequences, especially long terminal repeat retrotransposons, are prevalent in the T. yunnanensis genome, contributing to its large genome size. We further integrated genomic and transcriptomic data to unveil clusters of genes involved in Taxol synthesis, located on the chromosome 12, while gene families encoding hydroxylase in the Taxol pathway exhibited significant expansion. Our study contributes to the further elucidation of gymnosperm relationships and the Taxol biosynthetic pathway., Song, Fu, Yang, Niu, Tian, et al. present a high-quality genome assembly and transcriptome data of Taxus yunnanensis, a plant belonging to the Taxus genus known for sources of traditional medicine and natural anticancer drugs. This study explores the Taxus evolutionary history and sheds light on the Taxol biosynthetic pathway.

The ancient gymnosperm genus Taxus is the exclusive source of the anticancer drug paclitaxel, yet no reference genome sequences are available for comprehensively elucidating the paclitaxel biosynthesis pathway. We have completed a chromosome-level genome of Taxus chinensis var. mairei with a total length of 10.23 gigabases. Taxus shared an ancestral whole-genome duplication with the coniferophyte lineage and underwent distinct transposon evolution. We discovered a unique physical and functional grouping of CYP725As (cytochrome P450) in the Taxus genome for paclitaxel biosynthesis. We also identified a gene cluster for taxadiene biosynthesis, which was formed mainly by gene duplications. This study will facilitate the elucidation of paclitaxel biosynthesis and unleash the biotechnological potential of Taxus.

Natural regeneration of Taxus baccata L. is constrained due to the depth of seed dormancy requirements (often taking two or more years) and low seed germination. Further, the conventional method of vegetative propagation by cuttings is associated with difficulties in rooting. Hence, for the first time, this study describes an efficient and reproducible in vitro protocol for breaking the dormancy of seeds from the endangered forest tree T. baccata L. via zygotic embryo culture. Embryos isolated from 100% sterile seeds were cultured on DCR medium that contains sucrose (30 g/l), agar (8 g/l), and activated charcoal (5 g/l), fortified with different concentrations of Plant Growth Regulators (PGRs), and held at a temperature of 25 ± 2 ºC in a growth room. The results revealed that the in vitro embryo germination percentage was mostly affected by gibberellic acid (GA3) and thidiazuron (TDZ). Among the nine treatments, the treatments with 0.5 mg/l TDZ and 1 mg/l GA3 showed the highest germination (100%), while the other treatments all increased the germination percentages significantly compared to the control (37.5%). The 1/2 DCR medium with the addition of 0.1 mg/l indole-3-butyric acid (IBA) resulted in the highest rooting ratio (94%). However, the greatest root and hypocotyl elongation (59.37 ± 3.77 and 62.75 ± 4.43 mm, respectively) occurred when seedlings were cultured on 1/2 DCR medium containing 0.5 mg/l BA. Plantlets were transplanted into plastic pots containing an autoclaved garden soil, sand, and vermiculite mixture (1:1:1) and held at a temperature of 25 ± 2 ºC in a growth room for 4 weeks before being transplanted into the greenhouse. These results indicated that the protocol developed during the current study will be useful to overcome seed dormancy and for multiplication and conservation of the species T. baccata L.

Himalayan yew (Taxus baccata subsp wallichiana) produces Taxol (an anticancer drug) and therefore is of commercial importance. Yew is slow growing, exhibits poor regeneration rate, low survival percentage and has long seed dormancy period low viability potential. Overexploitation of Taxus has forced scientist to think of alternative measures for growing Taxus without compromising with Taxol extraction from the plant. Hydroponics is a good method for growing plants and the same was targeted in our study. The design was to grow yew cuttings in Hoagland’s medium as nutrition medium for growing Taxus with auxin (NAA, IAA, and IBA) in 250 mg/l, 500 mg/l, 1000 mg/l, 2000 mg/l, and 5000 mg/l concentration supplemented in the medium for 16 weeks. The control plants died after 16 weeks but the auxin supplemented medium kept yew cuttings alive and resulted in increase in shoot length. On average, the yew cuttings gained an increase of more than 80 % in yew cuttings for 16 weeks. From the experiment, it was deduced that auxin in the range of 250–2000 mg/l enhances the shoot length better than higher concentration. It was seen from the comparative data between eight to 16 weeks that the percentage of increase in height of yew cutting at 5000 mg/l is 7 % for IBA, 17 % for IAA and 14 % for NAA, clearly depicting that IAA and NAA are better Auxins for eliciting growth of Yew in stress condition. This strategy can work for the conservation of Taxus baccata for its ex situ conservation.

Taxus species have attracted much attention for their potency in cancer treatment. However, investigating the bioactivities of Taxus species is a complex task, due to their diversity, slow growth, and endangered state. The most important Taxus species in China are Taxus chinensis (T. chinensis), Taxus cuspidata (T. cuspidata), and Taxus × media (T. media), which mainly grow in the northeastern region. This article probes deep into the differences among the leaves of T. chinensis, T. cuspidata, and T. media, with the aid of gas chromatography-mass spectrometry (GC-MS). Through GC-MS, 162 compounds were detected in the samples and found to contain 35 bioactive metabolites. On this basis, 20 metabolites with significant bioactivities (antibiotic, antioxidant, anticancer, and antiaging effects) were identified via unsupervised learning of principal component analysis and supervised learning of partial least squares-discriminant analysis. The results show that T. media has the most prominent antibiotic, antioxidant, and anticancer effects, while T. cuspidata has the most diverse and abundant metabolites that slow down aging.

Taxol (Paclitaxel), an important anticancer drug, is derived at very low yields from Taxus (yew) species that grow very slowly. In the present study, thirteen genes that encode enzymes involved in Taxol biosynthesis in Taxus spp. were analyzed with bioinformatics methods, and their expression levels in different tissues and after cold and hormone treatments were also analyzed. The results indicated that many cis-elements related to abiotic stresses and hormones were found in the promoter sequences of the 8 genes involved in Taxol biosynthesis. Moreover, the 13 enzymes encoded by the target genes were located in different organelles and had many phosphorylation sites in the response proteins. The 13 genes were expressed highly either in roots or in stems, with lower transcripts in needles, and they were highly expressed after treatment with cold, gibberellin, methyl jasmonate or coronatine, consistent with predictions based on the bioinformatics analysis. These results suggest that the factors such as hormones and abiotic stresses stimulate taxane biosynthesis in yews, providing an important way to sustainably generate taxanes from yew trees or their cell cultures to improve Taxol yields.

English yew (Taxus baccata) is one of the few gymnospermous species present in the Hyrcanian forests, and it is listed as a rare and endangered species prone to extinction in Iran. This study aims to determine the ecological capability of Taxus baccata in the Hyrcanian region by identifying the diversity of plant communities dominated by this species, and to compare their floristic composition with the Taxus communities of southern Europe (Sicily, Corsica, Sardinia). We collected 408 releves in the central and eastern part of the Hyrcanian forests. The classification of plant communities was performed using TWINSPAN. Phi-coefficient index, constancy ratio, and the ratio of average cover were used to determine diagnostic species in each vegetation unit. The expert system language of the JUICE program was applied to create formal definitions for syntaxa. The relationship between species and environmental factors were investigated with DCA. The environmental differences among the syntaxa were also tested with one-way ANOVA. Sums of constancy and average species cover of the diagnostic species of classes according to the EuroVegChecklist were computed. We distinguished five associations within three alliances. Of these, two associations and one alliance are new for science. Annual precipitation, elevation and annual temperature which are affected by elevational as well as longitudinal gradients were found to be important factors affecting the diversity of Hyrcanian Taxus communities. The constancy sum of diagnostic species was the highest for the class Carpino-Fagetea sylvaticae in all Hyrcanian and European units except for one Taxus community in Sardinia. We conclude that the Hyrcanian and southern European Taxus communities are similar in their floristically and ecological properties. Yew communities in the central Hyrcanian forests are associated with humid temperate diagnostic species, while semi-humid temperate plants are frequent in the eastern Hyrcanian forests, similar to the yew communities in southern Europe.

The effect of the alkaloid extract of Taxus baccata (AETB) as a green inhibitor of carbon steel in 1M HCl solution, were assessed. It was found that the inhibition efficiency increased with the extract concentration and decreased with rising of temperature. The polarization curves revealed that the (AETB) acted as mixed type inhibitor. The extract was physisorbed on steel surface and obeys Langmuir’s model. Quantum chemical calculations and molecular dynamics simulation of the majority’s components existing in (AETB) were performed in order to correlate the electronic properties with their adsorption and inhibition behavior.

English yew is one of the most endangered species in Europe. Due to the specificity of this species, its natural regeneration is quite difficult. The aim of the study was to present the current situation of distribution, protection and restoration of the species in Ukraine. The study presents some characteristics of largest natural and artificial yew populations in the country and their protection. In situ and ex situ yew populations are quite different, in terms of bioclimatic conditions what does not affect to the growth characteristics of the populations. In addition, the activities related to the natural and artificial renaturalisation of the yew were analysed. Thus, tending of tree stands, where the natural regeneration of yew was inventoried can be recommended but it should be planned very individually regarding requirements of the site. The introduction of yew seedlings in the conditions of the managed forest is very difficult. Despite the complication of obtaining planting material and high cost, it is important measure to preserve the species. In Ukraine are successful examples of the seed transfer of yew populations by about 450 km in North-East direction (Carpathian yew population) and 700 km in North direction (Crimean yew population). It is an evidence of high ecological plasticity of the species. Moreover, some recommendations that could be useful for increasing the popularization of this species throughout the country were given in conclusions. The wider use of yew in public areas across the country due to unique value of species and more convenient protection of young seedlings. It is worth to continue the inventory of yew locations at the national level and study the possibilities to use as local sources to conservation of this species throughout the country.

The metabolic stimulation induced by abiotic stress is an efficient strategy for the production of secondary metabolites in sterile and controlled plant cell, tissue, and organ cultures. Paclitaxel (taxol), one of the most widely used therapeutic compounds for the treatment of various cancers, is mainly produced through cell culture of the European yew (Taxus baccata L.). In this work, a T. baccata callus culture was subjected to drought stress induced in vitro by mannitol and sorbitol (1, 2, 3, and 4%) and sucrose (6 and 8%) to evaluate its impact on physiological and biochemical traits as well as paclitaxel and 10-deacetyl baccatin III (10-DBA) production. It was observed that drought stress caused a significant increase (P < 0.05) in dry weight, proline, soluble sugars, hydrogen peroxide, lipid peroxidation, total phenolics, flavonoids, and flavonols, and a decrease in relative water content, fresh weight, relative growth rate, and cell viability. Constitutive activities of superoxide dismutase, guaiacol peroxidase, ascorbate peroxidase, and glutathione reductase were enhanced by the induced stress. The content of paclitaxel and 10-DBA was higher in stressed cultures than in the control. It can be concluded that T. baccata cells have a protection mechanism against oxidative damage involving induced activities of enzymatic and non-enzymatic antioxidants. The induction of moderate drought stress could therefore be an effective strategy for increasing taxanes production in T. baccata callus cultures.

Context Polysaccharide of Taxus chinensis var. mairei Cheng et L.K.Fu (Taxaceae) (PTM) functions in anti-apoptosis and antioxidation, but its function on Alzheimer’s disease (AD) remains unclear. Objective To investigate the effect of PTM on AD. Materials and methods C57BL/6J mice were randomly divided into three groups: control, d-galactose (d-gal), and d-gal + PTM. AD-like symptom was induced by d-gal for 6 weeks, followed with PTM (0.4 g/kg/d) for 14 days. PTM was added to BV2 cells stimulated with d-gal (1, 10, 20, 50, 100 and 500 μg/mL). Cell viability was evaluated by MTT assay. The expression of NRF2, SOD, cleaved caspase-3, Bax and Bcl-2 were detected with Western blot analysis. Cognitive function was evaluated by Morris water maze test. Results Decreased cleaved caspase-3 (1.30 ± 0.09) and Bax/Bcl2 ratio (1.32 ± 0.11) were observed in BV2 cells induced by d-gal + PTM (50 μg/mL). Increased MDA and ROS and decreased SOD were observed in d-gal group. However, decreased MDA (175 ± 9 ng/mL) and ROS level (188 ± 38 ng/mL) were observed after treated with PTM group (p

Taxol, a phyto-extracted diterpenoid, is the most commercially needed drug in cancer chemotherapy. In spite of the microbial production of taxol being successful and prospective, the reported yields are still not sufficient for large-scale production. Thus, the discovery of new taxol-producing microbial strains and production enhancement methodologies such as process optimization, strain improvement, and immobilization technique are the main objectives. In this paper, a taxol-producing start strain Epicoccum nigrum TXB502 (initial yield 61.35 μg L-1) was isolated from Taxus baccata and identified by morphological and molecular tools. The optimum cultivation and nutritional conditions were assessed by testing one parameter at a time approach that resulted in 88.59% significant production increase. In addition, a stable mutant with improved productivity (40.07% yield increase in comparison with the parent strain) was successfully developed after gamma irradiation mutagenesis of the start strain. The taxol titer was further improved via testing different immobilization carriers for both spores and mycelia of this mutant. Over taxol production was achieved using alginate-immobilized mycelia with the feasibility of conducting six successive production cycles in a semi-continuous form. The final total concentration reached 8187.77 μg taxol 6 L-1 which represents approximately 22-fold increase, as compared to the initial titer of the start strain. These findings can pave the way for the prospective industrial manufacturing of taxol, as the achieved taxol production in this study is the highest reported by academic laboratories for microbial cultures. KEY POINTS: • Discovery of a new taxol-producing endophytic fungus E. nigrum TXB502 strain. • Taxol yield was successfully improved via bioprocess optimization and strain mutagenesis. • Alginate-immobilized mycelia were efficient for a semi-continuous production of taxol. • The final total concentration of taxol showed approximately 22-fold increase as compared to the initial titer.

Not Available Plant Tissue Cult. & Biotech. 30(1): 161-166, 2020 (June)

Purpose Paclitaxel is a generic drug produced based on Taxol which is an extract of Taxus tree, well known for its anticancer and antibacterial effects. This study was aimed at building up an agent with the antibacterial and anticancer benefits of both the silver ions and Taxol, together with less cytotoxic effects. Materials and methods Colloidal silver nanoparticles (AgNPs) were synthesized by reducing aqueous AgNO3 with aqueous Taxus leaf extract at nonphotomediated conditions, without any catalyst, template or surfactant. The AgNP production was confirmed by ultraviolet-visible (UV-VIS) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier-transform infrared (FTI) spectroscopy. The MTT assay for human breast cancer cells as well as the DAPI fluorescent staining microscopy tested the biocompatibility and anticancer effects of AgNPs, silver nitrate, and Taxol. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) techniques were performed to determine the shape and size of the nanoparticles. MTT assay showed the best inhibitory concentration of AgNPs on cancer cells. The antibacterial activity of the three case study materials was tested for gram-positive (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) using well diffusion test. Results This work proposes more anticancer effects for AgNP made by Taxus brevifolia extract, comparing Taxol solution. IC50 was observed as 3.1 mM for Taxol while 1.5 mM for new AgNP. Moreover, Taxus showed no antibacterial effects while the new AgNP showed a dose-dependent biocompatibility along with slightly more antibacterial effects (MIC: 1.6 and 6.6mM for gram-positive and -negative bacteria, respectively) comparing with silver nitrate solution (MIC: 1.5 and 6.2 mM for gram-positive and -negative bacteria, respectively). Conclusion The production of herbal-mediated silver nanoparticles may be an efficient substitution for the silver nitrate-based medicines with less side effects.

Summary Genome mining of Ascomycete sp. F53 (F53), a fungal endophyte of the traditional Chinese medicinal plant Taxus yunnanensis (Chinese yew), revealed 35 putative specialized metabolite biosynthesis gene clusters, one of which encodes a rarely seen tandem polyketide synthase pathway with close homology to azaphilone biosynthesis pathways. A novel compound, lijiquinone 1, was subsequently isolated from F53 and structurally and functionally characterized. The m/z 385 [M + H+]+ compound, comprised of a cyclohexenone side group attached to a core bicyclic ring, displayed cytotoxicity against human myeloma cells (IC50 = 129 μM), as well as antifungal activity against Candida albicans (IC50 = 79 μM) and Cryptococcus albidus (IC50 = 141 μM). Our results suggest that enzymes encoded on the lij gene cluster are responsible for the synthesis of 1 and that the medicinal properties of T. yunnanensis could be partially mediated by this novel azaphilone. This study highlights the utility of combining traditional knowledge with contemporary genomic approaches for the discovery of new bioactive compounds., Genome mining of Ascomycete sp. F53 (F53), a fungal endophyte of the traditional Chinese medicinal plant Taxus yunnanensis (Chinese yew), revealed 35 putative specialized metabolite biosynthesis gene clusters, one of which encodes a rarely seen tandem polyketide synthase pathway. We believe this is the pathway for the novel compound, lijiquinone, which was isolated from F53 and structurally and functionally characterised.

Taxus chinensis is a National level protected plant and has been for a long time, since it grows slowly and has low regenerative capacity. Consequently, no large base of raw material forest of taxus was formed. This study used Taxus chinensis as the study object, for analyzing the chemical composition of T. chinensis extract via fourier transform infrared spectroscopy (FT-IR) and gas chromatography/mass spectrometry (GC/MS). 37 types of chemical components were detected. These were mainly ethers (asarone, dibutyl phthalate, diisobutyl phthalate), alcohols (nerolidol, Myo-inositol, 4-C-methyl-, trans-Sinapyl alcohol), acids (3,4-dimethoxycinnamic acid, palmitic acid, oleic Acid), flavonoids (macckiain, formononetin), ketone (4-hydroxy-.beta.-ionone, pseudobaptigenin), phenols (methyleugenol), esters (triacetin), aldehydes (sinapinaldehyde), and pyridines (alpha-methylstyrene). This chemical component could be directly or indirectly used for bioengineering, pharmaceutical engineering, the cosmetic industry, and other chemical industries. Keywords: Taxus chinensis, Extract, Function, FT-IR, GC/MS

Taxus stem barks can be used for extraction of paclitaxel. However, the composition of taxoids across the whole stem and the stem tissue-specificity of paclitaxel biosynthesis-related enzymes remain largely unknown. We used cultivated Taxus media trees for analyses of the chemical composition and protein of major stem tissues by an integrated metabolomic and proteomic approach, and the role of TmMYB3 in paclitaxel biosynthesis was investigated. The metabolomic landscape analysis showed differences in stem tissue-specific accumulation of metabolites. Phytochemical analysis revealed that there is high accumulation of paclitaxel in the phloem. Ten key enzymes involved in paclitaxel biosynthesis were identified, most of which are predominantly produced in the phloem. The full-length sequence of TmMYB3 and partial promoter sequences of five paclitaxel biosynthesis-related genes were isolated. Several MYB recognition elements were found in the promoters of TBT, DBTNBT and TS. Further in vitro and in vivo investigations indicated that TmMYB3 is involved in paclitaxel biosynthesis by activating the expression of TBT and TS. Differences in the taxoid composition of different stem tissues suggest that the whole stem of T. media has potential for biotechnological applications. Phloem-specific TmMYB3 plays a role in the transcriptional regulation of paclitaxel biosynthesis, and may explain the phloem-specific accumulation of paclitaxel.

The article discusses contemporary bio-ecological condition of Taxus baccata L., as one of the endangered species, in its natural spreading area in Georgia, particularly, in Batsara National Reserve and in ornamental horticulture of eastern Georgia. We have studied the periods of bud opening, vegetation ending, starting and ending of cambium action, sprout woodening process, time and rate of growth in height, and regularities of accumulation-transformation of storage carbohydrates. The studies revealed that the Yew growth duration is affected by the snowless winter and frequent droughts increased in the last decades, as they cause the lack of water in soils and badly affect the plant growth. The study of sprout woodening, cambium action peculiarities and regularities of accumulation-transformation of storage carbohydrates, prove its strong ability of frost-resistance. The study of bio-ecological peculiarities of Taxus baccata L. and its wide introduction in ornamental horticulture, greened areas and forest cultures will be useful for conservation of this endangered species.

Taxol is a successful anti-cancer drug, which extensively studied in Taxus spp. However, microbial endophytes also reported as taxol producers, and especially fungal endophytes extensively studied for the taxol biosynthesis pathway. Although it was well considered, the taxol biosynthesis pathway remains undisclosed since its discovery in bacteria. To decipher this gap, we isolated and identified the endophytic bacteria such as Bacillus flexus strain DMTMMB08, Bacillus licheniformis strain DMTMMB10, and Oceanobacillus picturae strain DMTMMB24, which are unprecedented for taxol production. Subsequently, the genome annotation of these bacteria exhibited the isoprene biosynthesis pathway and terpene synthase profile. Feasibly, this is the very first report on taxol-producing endophytic bacteria from the non-Taxus host and solitary investigation on its genome analysis. The genomic insight into the bacterial system for taxol biosynthesis leads to understanding the terpene synthesis and evolution. This piece of work could expand our perception of the diversity of terpenes and their related natural products.

This paper report the volatile compounds identified in the leaf and wood essential oil hyrdrodistilled from Taxus chinensis (Rehder & E.H. Wilson) Rehder (Taxaceae) from Vietnam. The chemical const...

The commercial production of paclitaxel; the most potent anti-cancer drug, is based on its extraction from Taxus spp (yews) or microbial fermentation from yews’ endophytes. The present study invest...

Background Gymnosperms represent five of the six lineages of seed plants. However, most sequenced plant mitochondrial genomes (mitogenomes) have been generated for angiosperms, whereas mitogenomic sequences have been generated for only six gymnosperms. In particular, complete mitogenomes are available for all major seed plant lineages except Conifer II (non-Pinaceae conifers or Cupressophyta), an important lineage including six families, which impedes a comprehensive understanding of the mitogenomic diversity and evolution in gymnosperms. Results Here, we report the complete mitogenome of Taxus cuspidata in Conifer II. In comparison with previously released gymnosperm mitogenomes, we found that the mitogenomes of Taxus and Welwitschia have lost many genes individually, whereas all genes were identified in the mitogenomes of Cycas, Ginkgo and Pinaceae. Multiple tRNA genes and introns also have been lost in some lineages of gymnosperms, similar to the pattern observed in angiosperms. In general, gene clusters could be less conserved in gymnosperms than in angiosperms. Moreover, fewer RNA editing sites were identified in the Taxus and Welwitschia mitogenomes than in other mitogenomes, which could be correlated with fewer introns and frequent gene losses in these two species. Conclusions We have sequenced the Taxus cuspidata mitogenome, and compared it with mitogenomes from the other four gymnosperm lineages. The results revealed the diversity in size, structure, gene and intron contents, foreign sequences, and mutation rates of gymnosperm mitogenomes, which are different from angiosperm mitogenomes.

A Gram-staining-positive, aerobic, rod-shaped, endospore-forming bacterium, designated strain M5HDSG1-1T, was originally isolated from a surface-sterilized root of Taxus chinensis (Pilger) Rehd. in Guizhou, PR China. This bacterium was tested by a polyphasic approach to determine its taxonomic position. A 16S rRNA gene-based phylogenetic analysis revealed that M5HDSG1-1T had the greatest similarity to the type strain of Bacillus nealsonii DSM 15077T (99.1 %). The average nucleotide identity values between M5HDSG1-1T and Bacillus nealsonii DSM 15077T and Bacillus circulans NBRC 13626T were 73.3 and 72.8 %, respectively. The digital DNA-DNA hybridization values between M5HDSG1-1T and Bacillus nealsonii DSM 15077T and Bacillus circulans NBRC 13626T were 20.1 and 20.6 %, respectively, which were below the recommended thresholds. M5HDSG1-1T grew at a pH range of 6.0-12.0 (optimum, 7.0-8.0), at temperatures between 10 and 45 °C (optimum, 30 °C) and at 0-2 % (w/v) NaCl (optimum, 1 %). Neither substrate nor aerial mycelia was formed, and no diffusible pigments were observed on the media tested. The predominant isoprenoid quinone was menaquinone-7 (MK-7). The major fatty acids were anteiso-C15 : 0, and iso-C15 : 0. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminophospholipid and an unidentified phospholipid. The DNA G+C content was 37.5 mol%. According to the phylogeneic, phenotypic and chemotaxonomic data, M5HDSG1-1T was clearly distinguishable from other species with validly published names in the genus Bacillus and should therefore be classified as representing a novel species, and we suggest the name Bacillus taxi sp. nov. The type strain is M5HDSG1-1T (=JCM 33117T=CGMCC 1.13668T).

Paclitaxel is a powerful anticancer alkaloid, which is widely used for treating various cancer types. However, its limited supply is the main impediment to its clinical use. Paclitaxel semisynthesis involves the isolation of paclitaxel intermediates from Taxus spp. needles. Also, the extraction process of the precursors is difficult and costly. The chemical synthesis of paclitaxel is not considered economically practical, because of its high cost and complex structure. While engineering long and highly complex pathway of paclitaxel biosynthesis in heterologous hosts is very challenging, plant cell culture named green cell factory is a promising biotechnological platform that can pave the way for commercializing paclitaxel production. The low yield of paclitaxel is an important challenge in its commercial production via cell culture. Strategies including selection of high-producing cell lines, optimization of cultural conditions, precursor feeding, elicitation, biosynthesis pathway engineering and demethylation, and immobilization have been used for improving paclitaxel biosynthesis in Taxus in vitro cell culture. Inducing paclitaxel biosynthesis pathway by different elicitors is the most effective strategy for enhancing its biosynthesis in cell culture platform. Also, the co-culture of Taxus or Corylus avellana cells with paclitaxel-producing endophyte(s) is promising for paclitaxel supply. High paclitaxel accumulation in cells leads to negative feedback, which is considered to be a drawback for its high production. Therefore, reinforcement of paclitaxel secretion system and in situ product removal from the culture media can increase paclitaxel productivity. Mathematical modeling of paclitaxel biosynthesis provides the efficient guidance for its biosynthesis enhancement in plant in vitro culture.

Paclitaxel, an important diterpenoid with a taxane skeleton, is isolated from Taxus species (yew tree), and used as a component of anticancer drugs. The U.S Food and Drug Administration (FDA) has approved paclitaxel for treating many cancer types, such as breast, lung and ovarian cancers and Kaposi’s sarcoma. Furthermore, it is also known as a crucial agent for arterial stents to prevent the formation of scar tissues. Yew trees grow slowly, and yield low levels of paclitaxel (0.01%–0.03% of the dry weight), and hence extracting paclitaxel from the trees on a large scale is very challenging. Recently, a great number of yew trees have been destroyed by humans for the extraction of this important drug. Therefore, alternative ways, including metabolic engineering approach should be explored to enhance the production of paclitaxel. For instance, abiotic and biotic elicitors are generally employed to enhance the production of pharmaceutical terpenoids. Several research groups have successfully identified few effective elicitors, including coronatine, salicylic acid (SA), methyl jasmonate (MJ) and abscisic acid to induce paclitaxel accumulation in suspension cell lines. The biotic elicitor MJ, known for regulating plant defense was found as a very effective molecule to induce overproduction of paclitaxel in Taxus cell suspension cultures. In addition to elicitors, higher paclitaxel production was observed in bioreactors through co-culturing of Taxus cells with its endophytic fungi. In previous studies, many genes and enzymes involved in the biosynthetic pathways of taxanes have been partially identified in Taxus species tissues and cells. Overexpression of genes involved in paclitaxel synthesis is another remarkable tactic to enhance the production of this target drug. In this chapter, molecular engineering strategies such as elicitors, overexpression of genes involved in paclitaxel biosynthesis, and ectopic expression to produce higher amounts of paclitaxel are discussed.

Taxus baccata (yew) is an easily accessible plant that can cause rapidly fatal cardiotoxicity upon ingestion. While it has been documented as both a method of suicide and homicide, such cases may b...

Taxol is a rare secondary metabolite that accumulates considerably in Taxus species under salicylic acid (SA) and methyl jasmonate treatment. However, the molecular mechanism of its accumulation remains unclear. We investigated TcWRKY33, a nuclear-localized group I WRKY transcription factor, as an SA-responsive regulator of taxol biosynthesis. Overexpression and RNA interference of TcWRKY33 confirmed that TcWRKY33 regulates the expression of most taxol biosynthesis genes, especially 10-deacetylbaccatin III-10-O-acetyltransferase (DBAT) and taxadiene synthase (TASY), which were considered as key enzymes in taxol biosynthesis. Transient overexpression of TcWRKY33 in Taxus chinensis leaves resulted in increased taxol and 10-deacetylbaccatin accumulation by 1.20 and 2.16 times compared with the control, respectively. Furthermore, TcWRKY33, DBAT, and TASY were confirmed to respond positively to SA signals. These results suggested that TcWRKY33 was the missing component of taxol biosynthesis that responds to SA. The sequence analysis identified two W-box motifs in the promoter of DBAT but not in the TASY. Yeast one-hybrid and dual-luciferase activity assays confirmed that TcWRKY33 can bind to the two W-boxes in the promoter of DBAT, upregulating its expression level. Hence, DBAT is a direct target of TcWRKY33. Furthermore, TcERF15, encoding a TASY activator, also contains two W-boxes in its promoter. Yeast one-hybrid and dual-luciferase activity assays further confirmed that TcWRKY33 can upregulate TASY expression through the activation of TcERF15. In summary, TcWRKY33 transmits SA signals and positively regulates taxol biosynthesis genes in two ways: directly and through the activation of other activators. Therefore, TcWRKY33 is an excellent candidate for genetically engineering regulation of taxol biosynthesis in Taxus plants.

Background and Objectives: Continuous and indiscriminate use of chemical drugs causes an essential resistance to microorganisms. By creating this phenomenon, the effect of drugs is weakened or neutralized, and finally causes an increase in the amount of drug consumption and the tendency to use compounds with newer and stronger formulations. On the other hand, it has been reported that many plants essential oils have a significant inhibitory effect on pathogenic microorganisms, so in this study, we tried to evaluate the antimicrobial activity of some medicinal plants on some standard human pathogenic bacteria and Candida albicans fungi isolated from women. Methods: Leaves of Cichorium intybus L., Hypericum perforatum L., Lavandula angustifolia, Thymus vulgaris L., and Taxus baccata L. were collected and also were determined in the botanical laboratory of the University of Zabol. Forty g of dried leaves in 400 cc of ethanol were used to prepare the ethanolic extract. Standard bacteria and fungi were obtained from the center for genetic and biological resources of Iran. To determine the activity of free radical trapping, diphenylpicryl hydrazyl was used and then the antimicrobial effects were investigated by diffusion method in Muller-Hinton agar medium using 6 mm paper disks according to Bauer and Kirby instructions. Statistx ver10 software was used for statistical calculations. Mean comparisons were performed using the LSD at the 1% level and Excel was also used to draw the shapes. Results: The diameter of the inhibitory zone of plant extracts against standard bacteria and clinical fungi of Candida albicans at a dilution of 100 ppm was analyzed and found to have different effects (p

The yew forest of Paterzell, one of the biggest yew (Taxus baccata L.) populations in Europe, is situated in the Bavarian pre-Alpine lowlands 50 km southwest of Munich in the area of the former Amm...

Background Taxus baccata, also known as English yew, is a poison that causes cardiac arrhythmias and can result in death from cardiogenic shock. Case summary A 49-year-old gentleman was admitted following yew ingestion with suicidal intent. He was bradycardic at 30 b.p.m. and hypotensive on arrival. Electrocardiography revealed complete heart block with broad complex ventricular escape rate of 30 b.p.m. Bedside echocardiography revealed severe global impairment of right and left ventricular systolic function. Urgent temporary transvenous pacing was instituted, and the patient was considered for veno-arterial extracorporeal membrane oxygenation. Unfortunately, he deteriorated rapidly and cardiorespiratory arrest ensued, and despite prolonged in-hospital resuscitation, the patient died. Post-mortem examination revealed small needle-shaped plant leaves together with seeds found in the stomach. Ante mortem serum sample analysis sent to the Royal Botanical Gardens and revealed the presence of taxine Type B alkaloids in the patient’s blood. Discussion Yew poisoning is a rare occurrence, and there is currently no effective antidote. Treatment involves supportive management, comprising prolonged effective cardiopulmonary resuscitation, pacing, and mechanical cardiac support. This case illustrates the importance of prompt recognition of yew poisoning, alongside early consideration of pacing and mechanical cardiac support. Due to the rarity of this cause of heart block, and since patients may not always volunteer a history of yew ingestion, yew poisoning is something that physicians should be aware of and this should be considered in the differential diagnosis in patients with unexpected heart block. Serum analysis for taxine alkaloids can be used to confirm the diagnosis.

In this study, we developed an ultrasound-assisted fractional precipitation for the purification of poorly water-soluble anticancer agent paclitaxel. The effects of ultrasound power (80, 180, 250, and 380 W) were investigated in samples of different purity (20.4, 63.6, and 92.7%) for precipitation. Higher precipitation rate and shorter precipitation time were found with ultrasound treated solutions than with those without ultrasound. When the experimental data were applied to the Johnson-Mehl-Avrami-Komolgorov (JMAK) equation, the rate constant increased to 200–500-fold for 20.4% of sample purity, 150–250-fold for 63.6% of sample purity, and 60–120-fold for 92.7% of sample purity by treatment with ultrasound. In addition, the lower the purity of the sample, the greater was the decrease in activation energy compared with the control, which means that the lower the sample purity, the more effective the fractional precipitation using ultrasound.

Taxus chinensis is a well-known gymnosperm with great ornamental and medicinal value. Its purple red brown heartwood (HW) has many attributes such as straight texture, high density, mechanical strength, rich elasticity and corrosion resistance that is highly prized commercially. T. chinensis sapwood (SW), in comparison, lacks these important traits. At present, little is known about the differences of metabolites between the SW and HW in T. chinensis. Widely targeted metabolic profiling was performed to analyze the metabolic profiles of HW and SW in T. chinensis using Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (LC-EI-MS). A total of 607 metabolites were detected in HW and SW. Among them, 146 metabolites were significantly higher, and 167 metabolites significantly lower, in HW as compared to SW. These differential metabolites were mainly involved in metabolic pathways and biosynthesis of secondary metabolites, such as flavonoids, flavone and flavonol, phenylpropanoids and antibiotics. Moreover, 71 flavonoids and isoflavones were found to be significantly different between HW and SW. Our results show the difference of components between the HW and SW, which has potential significance to further elucidate the mechanism of HW color formation. The results will provide insight into the metabolites associated with wood color formation and useful information for understanding the metabolites associated with wood quality.

A 53-year-old woman presented at our hospital due to nasal bleeding and petechiae with profound thrombocytopenia (0.4×109/L). Her platelet count returned to the normal range immediately following a platelet transfusion. In this case, tea brewed from Taxus yunnanensis was the only suspected agent ingested prior to the onset of thrombocytopenia while all other etiologies for thrombocytopenia were excluded. A re-exposure test to Taxus yunnanensis resulted in the recurrence of acute thrombocytopenia. The association of thrombocytopenia with substances other than drugs has so far only been rarely described and to the best of our knowledge, this is the first reported case of thrombocytopenia caused by Taxus yunnanensis.

Prostate cancer is fourth most abundant cancer type around the globe. Brevifoliol, a rearranged taxoid from Taxus walllichiana needles has been derivatized as C5 esters using Steglich esterification reaction. Seventeen diverse analogues were evaluated against a panel of human cancer cell lines by MTT assay. Among these, two of the semi-synthetic analogues, that is, 13 and 16 exhibited potent cytotoxicity, selectively against PC-3, prostate cancer cell lines. In cell cycle analysis, analogue 13 induced S and G2/M phase arrest and induced apoptosis by activating caspase-3. Compound 13 showed moderate efficacy in in-vivo Ehrlich ascites carcinoma in Swiss albino mice. Further, compound 13 was found to be safe in Swiss albino mice up to 1,000 mg/kg dose in acute oral toxicity. Brevifoliol ester 13 may further be optimized for better efficacy.

Dünyanın değişik bölgelerinde Taxus türlerinin pıhtılaşmayı önleyici, karaciğer koruyucu, antiülserojenik, antifungal ve tümör hücrelerinin oluşmasını ya da büyümelerini önleyici özellikleri olduğu anlaşılmıştır. Bu çalışma da Uşak ili Sivaslı ilçesinden toplanan Taxus Baccata türünün metanol ekstresinin yaprak, dal ve meyvesinde biyolojik aktivite çalışmaları yapılmıştır. “Taxus Baccata türünün metanol ekstresinde”, numunenin toplam fenolik içerik miktarı en yüksek yapraklarda 14,76 mg GA EQ / 1g kuru örnek olarak bulunmuştur. Taxus Baccata metanol ekstresinde, toplam flavonoid içerik miktarı en yüksek yapraklarda 0,468 ± mg QE/g kuru numune olarak belirlenmiştir. DPPH radikali olarak antioksidan aktivite değeri; yaprakta % inhibisyon değeri % 93,21 olarak bulunmuştur. Elde edilen bulgulara göre; Taxus Baccata L. bitkisinin yapraklarının meyve ve dallara nazaran daha yüksek antioksidan aktivite gösterdiği söylenebilir. İleri araştırmalarda Taxus Baccata türünün içerdiği kimyasal bileşenlerin belirlenmesinin ve daha detaylı araştırılmasının gerekli olduğu sonucuna varılmıştır.  

Production of the anticancer drug Taxol and its precursors in heterologous hosts is more sustainable than extraction from tissues of yew trees or chemical synthesis. Although attempts to engineer the Taxol pathway in microbes have made significant progress, challenges such as functional expression of plant P450 enzymes remain to be addressed. Here, we introduce taxadiene synthase, taxadiene-5α-hydroxylase, and cytochrome P450 reductase in a high biomass plant Nicotiana benthamiana. Using a chloroplastic compartmentalized metabolic engineering strategy, combined with enhancement of isoprenoid precursors, we show that the engineered plants can produce taxadiene and taxadiene-5α-ol, the committed taxol intermediates, at 56.6 μg g−1 FW and 1.3 μg g−1 FW, respectively. In addition to the tools and strategies reported here, this study highlights the potential of Nicotiana spp. as an alternative platform for Taxol production., Engineering Taxol pathway in microbes needs to overcome the difficulty of expressing plant P450 enzymes. Here, the authors use a compartmentalized metabolic engineering strategy to construct the taxanes production pathway in chloroplasts of Nicotiana benthamiana and realize the production of taxadience-5α-ol.

The mating system is a central parameter of plant biology because it shapes their ecological and evolutionary properties. Therefore, determining ecological variables that influence the mating system is important for a deeper understanding of the functioning of plant populations. Here, using old concepts and recent statistical developments, we propose a new statistical tool to make inferences about ecological determinants of outcrossing in natural plant populations. The method requires codominant genotypes of seeds collected from maternal plants within different locations. Using extensive computer simulations, we demonstrated that the method is robust to the issues expected for real-world data, including the Wahlund effect, inbreeding and genotyping errors such as allele dropout and allele misclassification. Furthermore, we showed that the estimates of ecological effects and outcrossing rates can be severely biased if genotyping errors and genetic differentiation are not treated explicitly. Application of the new method to the case study of a dioecious tree (Taxus baccata) allowed revealing that female trees that grow in lower local densities have a greater tendency towards mating with relatives. Moreover, we also demonstrated that biparental inbreeding is higher in populations that are characterized by a longer mean distance between trees and a smaller mean trunk perimeter. We found these results to agree with both the theoretical predictions and the history of English yew.

The present study investigated the endophytic biodiversity on different aged Taxus bark using highthroughput sequencing. Fungi from the five Taxus species, including Taxus yunnanensis, T. media, T. chinensis, and two unidentified Taxus species I and II, were identified by Internal Transcribed Spacer sequence analysis. The operational taxonomic units (OTUs) were 141, 114, 98, 67 and 36, respectively, while the genera numbers were 22, 14, 16, 9 and 10 from the species distribution data, respectively. The dominant fungal genera were Mycena (94.33%), Phageophora (43.97%) and Paraconiothyrium (34.02%), followed by Pestalotiopsis (1.58%) and Strelitziana (1.15%). Rankabundance curve and diversity index suggested that the major species from the bark of T. yunnanensis (YN) was endophytic fungi, whereas fungal species from the bark of unidentified Taxus species II (HDS 50) were quite rare. Furthermore, tree age notably influenced the bark endophytic fungal biodiversity.

Taxus chinensis var. mairei (Taxaceae) was collected from four distant populations of China. Stem parts were subjected to supercritical CO2 (SFE-CO2) extraction in an extraction apparatus and 0.03-...

Taxus baccata L., yew, is dioecious, small to medium-sized evergreen tree,native to Europe, Africa and Asia, but it is cultivated worldwide because of itsornamental features. It is long known that all parts of yew (except for aril) aretoxic, due to the alkaloid taxine. Nevertheless, some parts of yew tree can beused to treat cancer and as antimicrobial agents. Unlike its antibacterialproperties, antifungal activity of T. baccata is poorly investigated. In thisresearch, antifungal activity of yew methanolic and aqueous extracts was testedagainst Candida albicans ATCC 10231, Aspergillus brasiliensis ATCC 16404,and Ascosphaera apis MUCL 30769, through the agar well diffusion method.Leaves, bark and reproductive structures extracts were prepared separately formale and female plants. Unlike the aqueous, methanolic extracts caused variabledegree of fungal growth inhibition. The strongest inhibition was observed in theactivity of the aril extract against A. brasiliensis and C. albicans, with the activityof the male bark extract against A. apis following close. Considering theemerging multidrug resistance in C. albicans, an interesting finding is theinhibition of this species by all tested methanolic extracts, which is significantlystronger in comparison to the inhibition by standard antimycotic solution.According to the available data, male reproductive structures of this species werenot tested earlier for their antifungal activity, and our study showed high level ofantifungal activity of methanolic microstrobili extract. The realized researchindicates great antifungal potential of T. baccata, which should be furtherconfirmed by more comprehensive studies.

The goal of this study was to find significant pathways associated with fruit color in Taxus chinensis var. mairei. Two Taxus chinensis var. mairei with fruits of different colors were sequenced using high-throughput sequencing. Then, unigene assembly, unigene annotation, and classification of Clusters of Orthologous Groups of proteins (COGs) were performed. Gene ontology (GO) classification and pathway enrichment analysis for unigenes were also conducted. Protein coding sequences (CDS) were predicted. Subsequently, differentially expressed unigenes, functional enrichment pathways of differentially expressed unigenes, single nucleotide polymorphisms (SNPs), and simple sequence repeats (SSRs) were analyzed. The data of Taxus chinensis var. mairei were assembled into 45,112 unigenes with an average size of 1232 bp and an N50 of 1882 bp. The significantly enriched biological processes (BP) were metabolic processes, and cellular processes, followed by single-organism processes, and reproductive processes. Significantly enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were metabolic pathways, pathways related to the biosynthesis of secondary metabolites, and RNA transport pathways. Transition had a higher number of SNP sites than transversion. Trinucleotide had the highest SSR motif numbers. Metabolic pathways and the biosynthesis of secondary metabolites may play significant roles in determining fruit color in Taxus chinensis var. mairei. In addition, the present dataset would provide a basis for future functional genomic research on Taxus chinensis var. mairei.

The adsorption characteristics of paclitaxel from extracts of Taxus chinensis cell cultures by the commercial adsorbent Sylopute were investigated using different parameters such as initial paclitaxel concentration, adsorption temperature, and contact time. The equilibrium adsorption data were best represented with the highest accuracy (r2 > 0.984, RMSD